Sighting apparatus for ordnance.



min.

OR 19079 a7 +9 SIGHTING APPARATUS FOR ORDNANOE.

APPLICATION FILED JAN. 27, 1913. 1,079,749. Patented Nov. 25, 1913.

2 SHEETS-SHEET 1.

Inventors.-

COLUMBIA PLANOGRAPH CO-JVASMINOTON. n. C

A. T. DAWSON 6; G. T. BUGKHAM.

SIGHTING APPARATUS FOR ORDNANCE.

APPLICATION IILED JAN. 27, 1913.

Patented Nov. 25, 1913.

2 SHEETS-SHEET 2.

( ai'iikli'll ll 'IlllllllllIIIIIIII'IIJI'I Inventor:

' COLUMBIA PLANOGRAPH COUWASHINOTON. ILC.

88. AEQMETB MQAL GNSTRUMENTS.

UNITED STATES PATENT OFFICE.

ARTHUR TREVOR DAWSON AND GEORGE THOMAS BUCKHAM, OF WESTMINSTER, LONDON, ENGLAND, ASSIGNORS T0 VICKERS LIMITED, OF WESTMINSTER,

ENGLAND.

SIGHTING- APPARATUS FOR ORDNANCE.

To all whom it may concern:

Be it known that we, ARTHUR Tnnvon Dawson, knight, and GEORGE THOMAS BUCK- HAM, both subjects of the King of Great Britain, residing at Vickers House, Broadway, Westminster, in the county of London, England, have invented certain new and useful Improvements in or Relating to Sighting Apparatus for Ordnance, of WlllCll the following is a specification.

This invention relates to sighting apparatus, particularly sighting apparatus intended for use with high angle guns and of the kind in which the sight is under the control of a cam which is adapted to be automatically moved during the ranging and pointing operation in order to correct the line of sight for any particular range and altitude of the target without any previous setting of the sight.

According to this invention we so construct and arrange the cam in relation to the ranging and pointing gear of the gun, that the movements of the cam are automatically efl'ected during the ranging and pointing operations by means of mechanism which causes the cam to be angularly displaced during ranging to correct the sight for range, and to be axially displaced durin pointing to correct the sight for altltu e. The said cam may be carried by a movable frame or bracket connected by a link or other suitable means to the sight bracket, and may cooperate with member that moves during pointing only. We also provide improved means whereby the line of sight is automatically corrected for drift,

, the said meanstpcomprising a drift cam caried by\a member moved, by thegun n eleation and capable of lateral movement with respect to the. said member in order to dorrect the sight fordack of level of the gun cah'riage wheels.

In order that the said invention may be clearly understood and readily carried into effect, we will describe the same more fully with reference to the accompanying drawings in which Figure 1 is a side elevation, Fig. 2 a rear elevation and Fig. 3 a plan showing a form of sighting apparatus constructed in accordance with our invention. Fig. 4: is a section taken approximately on the line 1 1 of Fig, 1. Fig. 5 is an enlarged view of a part of Fig. 4, and Fig. 6 is a side elevation Specification of Letters Patent.

Application filed January 27, 1913.

Patented Nov. 25, 1913.

Serial No. 744,395.

with a part hereinafter referred to removed showing more clearly the cam and its cooperating parts.

In these figures, A is the sight, A the carrier on which it is mounted and A the bracket in which the said carrier is pivoted.

B represents the aforesaid cam, B" the frame or bracket connected to the sight bracket A and G the member moving during pointing only and cooperating with the cam B.

D represents the aforesaid member moved by the gun in elevation and D the drift cam carried thereby.

In the example illustrated, the frame or bracket B is connected by means of a link 6* with an arm a on the sight bracket A The aforesaid member C which moves with the gun during pointing only is, in the ex ample shown, in the form of an arm keyed or otherwise connected to a part C which is co-axial with the gun trunnion B and which moves only when the pointing hand Wheel C (Fig. 4:) is actuated. This hand wheel is arranged to the rear of the trunnions and on one side of the mounting, the ranging hand wheel (not shown) being on the other side of the mounting and co-aXial with the trunnions or in any other convenient position. The bracket B is loosely mounted on the part C and is capable of being angularly displaced by the arm C which is provided with a small hardened steel ball 0 (Figs. 1 and 6) that bears against the cam B; in order to insure that the cam and the arm are maintained in con tact, a spring 0* is interposed between the said arm and the bracket B Angular movement of the cam B (which as aforesaid occurs during ranging only) is effected by a spindle B (Figs. 4 and 5) having a portion of hexagonal cross section upon which a part 6 connected to the cam is slidably mounted. This spindle is carried by the bracket B and is provided with a pinion b that engages with the internal teeth of a quadrant B (Figs. 1, 4 and 5) keyed or otherwise secured to the gun trunnion B". Since the arm C moves during pointing only and the bracket B carrying the cam B and the spindle B moves therewith, there is no relative movement between the bracket B and the trunnion B during the pointing operation; consequently no relative movement takes place between the pinion 5 (carried by the bracket) and the quadrant B (secured to the trunnion). When however the gun is elevated for range the bracket LB remains stationary (since the arm C moves during pointing only) while the quadrant B continues to move with the gun, thereby causing the pinion its hexagonal spindle B and the cam B mounted on the spindle, to be angularly displaced during ranging only. The engagement of the angularly moving cam B with the arm G causes the loosely mounted bracket B to be angularly displaced and the sight, through the link 6*, the arm a", and the bracket A to be corrected for change of range.

Axial movement of the cam is, in the example shown, obtained from a cylinder or drum E having helical slots 6 in which engage the ends of a cross-head E formed on a sleeve 0 interposed between the part b and the cam B. The cam is free to rotate on the sleeve 6* but it cannot move axially thereon owing to the collar 6 and shoulder 6 This sleeve is keyed to a boss 13 on the bracket B and is thus free to slide axially but is prevented from rotating thereon. The cylinder or drum E is connected by a link 6 to the carriage, so that as the bracket B moves during pointing as aforesaid, the said cylinder or drum, owing to its connection with the carriage, is angularly displaced in the bracket B through the same angle as, but in the opposite direction to, the move ment of the gun during pointing; the link 6 thus forms a part of a parallel motion device. This angular displacement of the drum or cylinder causes the cross-head E together with the cam B to move axially by reason of the aforesaid helical slots 6. Thus it will be seen that the cam B moves axially during pointing only, and during this movement the portion of the surface of the cam that is correct for the given altitude is brought into contact with the arm C so that the sight is corrected for altitude. The cam and its operating parts are inclosed in a dust proof casing B which for clearness of illustration is removed in Fig. 6.

The carrier A for the sight (which is shown as being of the goniometric type) is mounted by means of a vertical pivot in the bracket A The carrier is provided with a forwardly extending arm a engaging with the aforesaid drift cam, which is in the form of a groove or slot D formed in a block D carried by the member D. This member D moves with the gun in elevation by reason of its being connected by a link d to an arm (1 on the quadrant B keyed to the trunnion. The member D", which is curved as shown in Fig. 3, is pivoted on the sight trunnion A. The said block D is pivoted by a pivot pin cl to the member D and is provided with suitable means of adjustment so that the slot D can always be maintained in its correct position to the vertical irrespective of the level of the carriage wheels. These adjusting means preferably comprise a worm (Z which is carried by the member D and which engages with a worm wheel segment D" attached to the spindle or pivot pin The shape of the slot D is such that the re quired corrections for drift can be imparted to the sight, a mean drift curve being preferably chosen. The slot is covered, to protect it from dust, by means of a curved plate D (Figs. 1 and 3) carried by the arm a of the carrier A. The relative movement between the arm a and the slot D takes place during the ranging of the gun, but by employing the mean drift curve, the errors due to neglecting the drift resulting from the altitude are inconsiderable.

What we claim as our invention and desire to secure by Letters Patent of the United States is 1. In sighting apparatus for ordnance, the combination with the sight, and the a11- gularly and axially movable cam for effecting the setting thereof, of a loosely mounted bracket carrying said cam, a member moving only during the pointing of the gun, said member bearing against the surface of the cam, means for angularly displacing said cam during the ranging of the gun and means for axially displacing the cam during the pointing of the gun.

2. In sighting apparatus for ordnance, the combination with the sight, its sight bracket and the angularly and axially movable cam for effecting the setting of the sight, of a loosely mounted bracket carrying said cam, a link connecting said bracket to the sight bracket, a member moving only during the pointing of the gun, said member bearing against the surface of the cam, means for angularly displacing said cam during the ranging of the gun and means for axially displacing the cam during the pointing of the gun.

3. In sighting apparatus for ordnance, the combination with the sight, its sight bracket and the angularly and axially movable cam for effecting the setting of the sight, of a loosely mounted bracket carrying said cam, a member moving only during the pointing of the gun, said member hearing against the surface of the cam, another member moving with the gun in elevation and means whereby the relative movement that takes place between said members during the ranging operation effects the angular movement of the cam.

4:. In sighting apparatus for ordnance, the combination with the sight, its sight bracket and the angularly and axially mov able cam for effecting the setting of the sight; of a loosely mounted bracket carry- I. qaomerazoaa memumsms,

ing said cam, a member moving only during the pointing of the gun, said member bearing against the surface of the cam, another member moving with the gun, means whereby the relative movement that takes place between said members during the ranging operation effects the angular movement of the cam, a rotary member which moves angularly when the pointing opera tion is performed, and means for causing said rotary member during its angular movement to displace the cam axially.

5. In sighting apparatus for ordnance, the combination with the gun, its trunnions, the sight, its sight bracket, and the angularly and axially movable cam for effecting the setting of the sight, of a loosely mounted bracket carrying said cam, an arm moving only during the pointing of the gun,

WI urn-n said arm bearing against the surface of the cam, a p adrant attached to one ofthe gun trunnions, a pini'on gearing witli said quadrant,aspindle with flat surfaces actuated by said pinion, means for slidably mounting the cam on said spindle, a rotary drum having helical slots therein, means for angularly displacing said drum during the ranging operation, and means for effecting the axial movement of the cam from the said helical grooves during the pointing operation.

In testimony whereof we aflix our signatures in the presence of two witnesses.

ARTHUR TREVOR DAWSON. GEORGE THOMAS BUCKHAM. WVitnesses HENRY KING, J NO. R. CAswELL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

